Degenerative Cervical Myelopathy: A Practical Approach to Diagnosis

Understanding degenerative cervical myelopathy in musculoskeletal practice

BACKGROUND

Degenerative cervical myelopathy (DCM) is a clinical syndrome characterized by a progressive compression of the spinal cord. DCM often looks like common symptoms of aging or bilateral carpal tunnel syndrome in its early stages, requiring careful differential diagnosis. Identifying DCM is a real challenge as no validated screening tools are available for making the DCM diagnosis. Potentially, individuals with DCM may experience misdiagnosis or substantial diagnostic delays, with an enhanced risk of irreversible neurological consequences if not promptly addressed. Despite the increasing prevalence, there is a lack of awareness about DCM among both the public and healthcare professionals. However, patients may seek physiotherapy to obtain a diagnosis or access treatment.

METHODS

A comprehensive (non-systematic) review of the literature about DCM epidemiology, pathophysiology, clinical presentation, diagnostic methods, and management was conducted.

RESULTS

A guide and essential knowledge to facilitate clinicians to understand DCM and to enhance clinical reasoning skills, performance and interpretation of the examination are provided. Interdisciplinary collaboration and optimal referral methods are also handled.

CONCLUSION

The aim of this article is to summarize and enhance physiotherapists' essential knowledge of the differential diagnosis and management of patients with DCM.

Clinical signs and symptoms for degenerative cervical myelopathy: a scoping review of case-control studies to facilitate early diagnosis among healthcare professionals with stakeholder engagement

STUDY DESIGN

Scoping Review.

OBJECTIVE

Degenerative cervical myelopathy (DCM) is a leading cause of chronic spinal cord dysfunction, with diverse clinical presentations that complicate diagnosis. Therefore, it is important to identify the signs and symptoms of DCM that demonstrate high diagnostic accuracy. This review aims to evaluate the sensitivity and specificity of signs and symptoms in diagnosing DCM.

METHODS

Articles up to June 2024 were retrieved from PubMed, EMBASE, and Cochrane databases using search terms like "degenerative cervical myelopathy", "cervical spondylotic myelopathy", "sensitivity", "specificity", and related signs and symptoms. Studies were screened based on selection criteria assessing the sensitivity and specificity of signs or symptoms using an appropriate control group.

RESULTS

Sixteen studies were included. The most sensitive signs were Tromner sign (93-97%) and hyperreflexia (15-85%). Specific signs included the Babinski sign (93-100%), Tromner sign (79-100%), clonus (96-99%), and inverted supinator sign (78-99%). Neck pain had a sensitivity of 76-94% and specificity of 11-73%. Hand incoordination showed 52% sensitivity and 92% specificity. Altered hand sensation had 76% sensitivity and 90% specificity. Upper extremity weakness had 51-75% sensitivity and 18-95% specificity. Gait imbalance exhibited 56-63% sensitivity and 52-95% specificity.

CONCLUSION

Sensitive signs like the Tromner sign and hyperreflexia are useful for screening, while specific signs such as Babinski, clonus, and the inverted supinator sign aid in confirmation of DCM. Symptoms like neck pain, hand incoordination, and altered hand sensation should heighten suspicion and guide differential diagnosis. Early and accurate diagnosis using these indicators can improve patient outcomes and reduce diagnostic delays.

Optimising early detection of degenerative cervical myelopathy: a systematic review of quantitative screening tools for primary care

Background

Early diagnosis of degenerative cervical myelopathy (DCM) is often challenging due to subtle, non-specific symptoms, limited disease awareness and a lack of definitive diagnostic criteria. As primary care physicians are typically the first to encounter patients with early DCM, equipping them with effective screening tools is crucial for reducing diagnostic delays and improving patient outcomes. This systematic review evaluates the efficacy of quantitative screening methods for DCM that can be implemented in primary care settings.

Methods

A systematic search following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines was conducted across PubMed, Embase and Cochrane Library up to July 2024 using keywords relevant to DCM screening. Studies were included if they evaluated the sensitivity and specificity of DCM screening tools applicable to primary care settings. Study quality was assessed using the Quality Assessment of Diagnostic Accuracy Studies-2 tool.

Results

The search identified 14 studies evaluating 18 screening methods for DCM. Questionnaires consistently showed high diagnostic accuracy, with Youden indices exceeding 0.60, while only three out of nine conventional physical performance tests met the same threshold. Sensor-assisted tests, particularly those using advanced technology like finger-wearable gyro sensors, exhibited the highest diagnostic accuracy but present challenges related to accessibility and learning curves.

Conclusion

This review highlights the potential of quantitative screening methods for early DCM detection in primary care. While questionnaires and conventional tests are effective and accessible, sensor-assisted tests offer greater accuracy but face implementation challenges. A tailored, multifaceted approach is crucial for improving outcomes. Future research should focus on validating these tools in diverse populations and standardising diagnostic criteria.

Epidemiology of Spinal Cord Injury and Associated Mortality, Past and Present. Is There a Difference?

BACKGROUND

The demographics of the population with spinal cord injury (SCI) have been dynamic over time, especially as a result of aging. This study investigated the patterns of SCI admissions by age in the United States over the past decade.

METHODS

Data were evaluated (2010-2021), from the National Spinal Cord Injury Model Systems records. Patients were compared based on age (<70 and ≥70 years), analysis of mortality, neurologic level of injury, neurologic improvement, mortality by American Spinal Injury Association (ASIA) grade, and neurologic level of injury. Patients older than 70 years were defined as elderly.

RESULTS

The mean age of the 8137 patients reviewed was 42.6 years (range, 15-88 years). The mean admission rate per year was 678 (range, 378-758). For the elderly versus the younger cohort, the incidence of falls decreased by 5% versus 3.3%, vehicle accidents increased by 3% versus 14%, high tetraplegia increased by 14.7% versus 22.5%, and low tetraplegia decreased by 12% versus 5.7%. In the elderly, ASIA grades A, B, and C decreased significantly, whereas ASIA grade D increased by 23.8%. In the younger cohort, ASIA grade A and B injuries decreased, whereas grades C and D increased, all <5%. Overall, 32.1% of those with ASIA grade A and 68% with ASIA grade B injuries improved within 1-2 years after injury. In-hospital and 1-year mortality decreased by 14.5% and 35.4%, respectively, in the elderly.

CONCLUSIONS

The incidence of SCI increased. High cervical and incomplete injuries increased, whereas complete SCIs declined. In-hospital and 1-year mortality decreased. There was recovery in select cases of complete SCIs within 1 year.

Degenerative Cervical Myelopathy: History, Physical Examination, and Diagnosis

Background: Degenerative cervical myelopathy is a progressive neurological disorder that is commonly encountered in clinical practice and its incidence is expected to increase alongside the aging population. Given the importance of early and accurate diagnosis in this patient population, this narrative review aims to provide a repository of up-to-date information regarding pertinent patient history, physical exam findings, and potential alternate diagnoses. Methods: The PubMed database was queried for publications from 1 January 2019 to 19 March 2024. The search terms utilized are as follows: cervical myelopathy", "cervical spondylotic myelopathy", "degenerative cervical myelopathy", "epidemiology", "prevalence", "incidence", "etiology", "diagnosis", "differential", "symptoms", "clinical presentation", and "atypical symptoms". The resultant articles were reviewed for relevance and redundancy and are presented within the following categories: Natural History, Epidemiology, Clinical Presentation, Diagnosis, and Management. Results: Myelopathy patients often present with subtle and non-specific symptoms such as sleep disturbances, increased falls, and difficulty driving, which can lead to underdiagnosis and misdiagnosis. Failing to diagnose degenerative cervical myelopathy in a timely manner can result in progressive and irreparable neurological damage. Although many nonoperative treatment modalities are available, surgical decompression is ultimately recommended in most cases to limit further deterioration in neurological function and optimize long-term patient outcomes. Conclusions: A thorough clinical history and physical examination remain the most important diagnostic tools to avoid misdiagnosis and implement early treatment in this patient population.

Cervical spinal cord morphometrics in degenerative cervical myelopathy: quantification using semi-automated normalized technique and correlation with neurological dysfunctions

BACKGROUND CONTEXT

Degenerative cervical myelopathy (DCM) is characterized by spinal cord atrophy. Accurate estimation of spinal cord atrophy is key to the understanding of neurological diseases, including DCM. However, its clinical application is hampered by difficulties in its precise and consistent estimation due to significant variability in spinal cord morphometry along the cervical spine, both within and between individuals.

PURPOSE

To characterize morphometrics of the compressed spinal cord in DCM patients. We employed our semiautomated analysis framework that incorporates the Spinal Cord Toolbox (SCT) and a normalization approach to effectively address the challenges posed by cord compression in these patients. Additionally, we examined the clinical relevance of these morphometric measures to enhance our understanding of DCM pathophysiology.

STUDY DESIGN

Prospective study.

PATIENT SAMPLE

This study investigated 36 DCM patients and 31 healthy controls (HCs).

OUTCOME MEASURES

Clinical scores including 9-hole peg test for hand dexterity, hand grip strength, balance, gait speed, modified Japanese Orthopaedic Association (mJOA) score, and imaging-based spinal cord morphometrics.

METHOD

Using the generic spine acquisition protocol and our semiautomated analysis pipeline, spinal cord morphometrics, including cross-sectional area (CSA), anterior-posterior (AP) and transverse (RL) diameters, eccentricity, and solidity, were estimated from sagittal T2w magnetic resonance imaging (MRI) images using the Spinal Cord Toolbox (SCT). Normalized metrics were extracted from the C1 to C7 vertebral levels and compared between DCM patients and HC. Morphometric data at regions of maximum spinal cord compression (MSCC) were correlated with the clinical scores. A subset of participants underwent follow-up scans at 6 months to monitor longitudinal changes in spinal cord atrophy.

RESULTS

Spinal cord morphometric data were normalized against the healthy population morphometry (PAM50 database) and extracted for all participants. DCM patients showed a notable reduction in CSA, AP, and RL diameter across all vertebral levels compared to HC. MSCC metrics correlated significantly with clinical scores like dexterity, grip strength, and mJOA scores. Longitudinal analysis indicated a decrease in CSA and worsening clinical scores in DCM patients.

CONCLUSION

Our processing pipeline offers a reliable method for assessing spinal cord compression in DCM patients. Normalized spinal cord morphometrics, particularly the CSA could have potential for monitoring DCM disease severity and progression, guiding treatment decisions. Furthermore, to our knowledge our study is the first to apply the generic spinal cord acquisition protocol, ensuring consistent imaging across different MRI scanners and settings. Coupled with our semiautomated analysis pipeline, this protocol is key for the detailed morphometric characterization of compressed spinal cords in patients with DCM, a disease that is both complex and heterogenous. This study was funded by the National Institute of Neurological Disorders and Stroke (NINDS) (K23:NS091430) and (R01: NS129852-01A1).

Imaging protocols for non-traumatic spinal cord injury: current state of the art and future directions

INTRODUCTION

Non-traumatic spinal cord injury (NTSCI) is a term used to describe damage to the spinal cord from sources other than trauma. Neuroimaging techniques such as computerized tomography (CT) and magnetic resonance imaging (MRI) have improved our ability to diagnose and manage NTSCIs. Several practice guidelines utilize MRI in the diagnostic evaluation of traumatic and non-traumatic SCI to direct surgical intervention.

AREAS COVERED

The authors review practices surrounding the imaging of various causes of NTSCI as well as recent advances and future directions for the use of novel imaging modalities in this realm. The authors also present discussions around the use of simple radiographs and advanced MRI modalities in clinical settings, and briefly highlight areas of active research that seek to advance our understanding and improve patient care.

EXPERT OPINION

Although several obstacles must be overcome, it appears highly likely that novel quantitative imaging features and advancements in artificial intelligence (AI) as well as machine learning (ML) will revolutionize degenerative cervical myelopathy (DCM) care by providing earlier diagnosis, accurate localization, monitoring for deterioration and neurological recovery, outcome prediction, and standardized practice. Some intriguing findings in these areas have been published, including the identification of possible serum and cerebrospinal fluid biomarkers, which are currently in the early phases of translation.

Updates in current concepts in degenerative cervical myelopathy: a systematic review

Background

The incidence of degenerative cervical myelopathy (DCM) has increased over the years due to an increasing aging population, yet there is a dearth of recent comprehensive data evaluating the multiple facets of this degenerative condition. Recent publications have highlighted the biochemistry and biomechanics of DCM, which are paramount to understanding the degenerative nature of the condition and selecting the most optimal treatment options for improved patient outcomes. In addition, there have been recent studies establishing the superiority of surgical to non-surgical treatments for DCM, which until now was a poorly substantiated claim that has permeated the medical field for decades. The authors of this systematic review sought to collect and assess available high quality peer reviewed data to analyze the nature of DCM and gain a better understanding for its treatment choices.

Methods

PubMed and Cochrane Central Register of Controlled Trials were systematically searched on January 19, 2023 with date restrictions of 2015-2023 imposed. For initial data collection, five independent searches were completed using the following keywords: pathogenesis, pathophysiology, and epidemiology of DCM; cervical spondylotic myelopathy (CSM) and DCM recent developments; management and treatment for CSM and DCM; diagnosis and management of DCM; and pathophysiology of DCM. The results were screened for their application to DCM; any study that did not directly address DCM were identified and removed through abstract assessment, such studies included those pertaining to alternative fields including cardiology and psychiatry. Studies found relevant through full-text assessment and those published in English were included in this study and unpublished studies and studies found irrelevant based on titles and keywords were excluded from this study. The 115 articles that met criteria were critically appraised independently by the 2 reviewers and the principles of Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) were applied to assess the quality of evidence from each study.

Results

A total of 352 studies resulted from the original search. There were 71 duplicate articles that were removed and a total of 281 articles were screened. 166 articles were then removed based on the exclusion/inclusion criteria, title, and abstract. Of the 138 articles that remained, a final list of 115 articles was created based on the reporting measures.

Conclusions

DCM is a multifactorial disease that has the potential to impair neurological function and cause significant paralysis. Although the multiple facets of this disease have not been fully elucidated, there have been significant breakthroughs in understanding the mechanisms involved in this disease process. The use of complex imaging modalities, genetic sequencing, biomarkers, and pharmacological agents has provided insight into the factors involved in the progression of DCM, which has consequently cultivated more refined approaches for diagnosis and treatment of DCM.

Evidence-based commentary on the diagnosis, management, and further research of degenerative cervical spinal cord compression in the absence of clinical symptoms of myelopathy

Degenerative cervical myelopathy (DCM) represents the final consequence of a series of degenerative changes in the cervical spine, resulting in cervical spinal canal stenosis and mechanical stress on the cervical spinal cord. This process leads to subsequent pathophysiological processes in the spinal cord tissues. The primary mechanism of injury is degenerative compression of the cervical spinal cord, detectable by magnetic resonance imaging (MRI), serving as a hallmark for diagnosing DCM. However, the relative resilience of the cervical spinal cord to mechanical compression leads to clinical-radiological discordance, i.e., some individuals may exhibit MRI findings of DCC without the clinical signs and symptoms of myelopathy. This degenerative compression of the cervical spinal cord without clinical signs of myelopathy, potentially serving as a precursor to the development of DCM, remains a somewhat controversial topic. In this review article, we elaborate on and provide commentary on the terminology, epidemiology, natural course, diagnosis, predictive value, risks, and practical management of this condition-all of which are subjects of ongoing debate.

The Frequency of Symptoms in Patients With a Diagnosis of Degenerative Cervical Myelopathy: Results of a Scoping Review

STUDY DESIGN

Delayed diagnosis of degenerative cervical myelopathy (DCM) is associated with reduced quality of life and greater disability. Developing diagnostic criteria for DCM has been identified as a top research priority.

OBJECTIVES

This scoping review aims to address the following questions: What is the diagnostic accuracy and frequency of clinical symptoms in patients with DCM?

METHODS

A scoping review was conducted using a database of all primary DCM studies published between 2005 and 2020. Studies were included if they (i) assessed the diagnostic accuracy of a symptom using an appropriate control group or (ii) reported the frequency of a symptom in a cohort of DCM patients.

RESULTS

This review identified three studies that discussed the diagnostic accuracy of various symptoms and included a control group. An additional 58 reported on the frequency of symptoms in a cohort of patients with DCM. The most frequent and sensitive symptoms in DCM include unspecified paresthesias (86%), hand numbness (82%) and hand paresthesias (79%). Neck and/or shoulder pain was present in 51% of patients with DCM, whereas a minority had back (19%) or lower extremity pain (10%). Bladder dysfunction was uncommon (38%) although more frequent than bowel (23%) and sexual impairment (4%). Gait impairment is also commonly seen in patients with DCM (72%).

CONCLUSION

Patients with DCM present with many different symptoms, most commonly sensorimotor impairment of the upper extremities, pain, bladder dysfunction and gait disturbance. If patients present with a combination of these symptoms, further neuroimaging is indicated to confirm the diagnosis of DCM.

The value of Clinical signs in the diagnosis of Degenerative Cervical Myelopathy - A Systematic review and Meta-analysis

STUDY DESIGN

Delayed diagnosis of degenerative cervical myelopathy (DCM) is likely due to a combination of its subtle symptoms, incomplete neurological assessments by clinicians and a lack of public and professional awareness. Diagnostic criteria for DCM will likely facilitate earlier referral for definitive management.

OBJECTIVES

This systematic review aims to determine (i) the diagnostic accuracy of various clinical signs and (ii) the association between clinical signs and disease severity in DCM?

METHODS

A search was performed to identify studies on adult patients that evaluated the diagnostic accuracy of a clinical sign used for diagnosing DCM. Studies were also included if they assessed the association between the presence of a clinical sign and disease severity. The QUADAS-2 tool was used to evaluate the risk of bias of individual studies.

RESULTS

This review identified eleven studies that used a control group to evaluate the diagnostic accuracy of various signs. An additional 61 articles reported on the frequency of clinical signs in a cohort of DCM patients. The most sensitive clinical tests for diagnosing DCM were the Tromner and hyperreflexia, whereas the most specific tests were the Babinski, Tromner, clonus and inverted supinator sign. Five studies evaluated the association between the presence of various clinical signs and disease severity. There was no definite association between Hoffmann sign, Babinski sign or hyperreflexia and disease severity.

CONCLUSION

The presence of clinical signs suggesting spinal cord compression should encourage health care professionals to pursue further investigation, such as neuroimaging to either confirm or refute a diagnosis of DCM.

Is Upper Extremity or Lower Extremity Function More Important for Patient Satisfaction? An Analysis of 24-Month Outcomes from the QOD Cervical Spondylotic Myelopathy Cohort

STUDY DESIGN

Retrospective analysis of a prospective, multicenter registry.

OBJECTIVE

To assess whether upper or lower limb mJOA improvement more strongly associates with patient satisfaction after surgery for cervical spondylotic myelopathy (CSM).

SUMMARY OF BACKGROUND DATA

The modified Japanese Orthopaedic Association (mJOA) is commonly used to assess functional status in patients with CSM. Patients present with upper and/or lower extremity dysfunction, and it is unclear whether improvement in one and/or both symptoms drives postoperative patient satisfaction.

METHODS

This study utilizes the prospective Quality Outcomes Database (QOD) CSM data set. Clinical outcomes included mJOA and North American Spine Society (NASS) satisfaction. The upper limb mJOA score was defined as upper motor plus sensory mJOA, and the lower limb mJOA as lower motor plus sensory mJOA. Ordered logistic regression was used to determine whether upper or lower limb mJOA was more closely associated with NASS satisfaction, adjusting for other covariates.

RESULTS

Overall, 1141 patients were enrolled in the QOD CSM cohort. In all, 780 had both preoperative and 24-month mJOA scores, met inclusion criteria, and were included for analysis. The baseline mJOA was 12.1±2.7, and postoperatively, 85.6% would undergo surgery again (NASS 1 or 2, satisfied). Patients exhibited mean improvement in both upper (baseline:3.9±1.4 vs. 24 mo:5.0±1.1, P<0.001) and lower limb mJOA (baseline:3.9±1.4 vs. 24 mon:4.5±1.5, P<0.001); however, the 24-month change in the upper limb mJOA was greater (upper:1.1±1.6 vs. lower:0.6±1.6, P<0.001). Across 24-month NASS satisfaction, the baseline upper and lower limb mJOA scores were similar (pupper=0.28, plower=0.092). However, as satisfaction decreased, the 24-month change in upper and lower limb mJOA decreased as well (pupper<0.001, plower<0.001). Patients with NASS scores of 4 (lowest satisfaction) did not demonstrate significant differences from baseline in upper or lower limb mJOA (P>0.05). In ordered logistic regression, NASS satisfaction was independently associated with upper limb mJOA improvement (OR=0.81; 95% CI: 0.68-0.97; P=0.019) but not lower limb mJOA improvement (OR=0.84; 95% CI: 0.70-1.0; P=0.054).

CONCLUSIONS

As the magnitude of upper and lower mJOA improvement decreased postoperatively, so too did patient satisfaction with surgical intervention. Upper limb mJOA improvement was a significant independent predictor of patient satisfaction, whereas lower limb mJOA improvement was not. These findings may aid preoperative counseling, stratified by patients' upper and lower extremity treatment expectations.

LEVEL OF EVIDENCE

Level-III.

Impaired communication at the neuromotor axis during Degenerative Cervical Myelopathy

Degenerative Cervical Myelopathy (DCM) is a progressive neurological condition characterized by structural alterations in the cervical spine, resulting in compression of the spinal cord. While clinical manifestations of DCM are well-documented, numerous unanswered questions persist at the molecular and cellular levels. In this study, we sought to investigate the neuromotor axis during DCM. We use a clinically relevant mouse model, where after 3 months of DCM induction, the sensorimotor tests revealed a significant reduction in both locomotor activity and muscle strength compared to the control group. Immunohistochemical analyses showed alterations in the gross anatomy of the cervical spinal cord segment after DCM. These changes were concomitant with the loss of motoneurons and a decrease in the number of excitatory synaptic inputs within the spinal cord. Additionally, the DCM group exhibited a reduction in the endplate surface, which correlated with diminished presynaptic axon endings in the supraspinous muscles. Furthermore, the biceps brachii (BB) muscle exhibited signs of atrophy and impaired regenerative capacity, which inversely correlated with the transversal area of remnants of muscle fibers. Additionally, metabolic assessments in BB muscle indicated an increased proportion of oxidative skeletal muscle fibers. In line with the link between neuromotor disorders and gut alterations, DCM mice displayed smaller mucin granules in the mucosa layer without damage to the epithelial barrier in the colon. Notably, a shift in the abundance of microbiota phylum profiles reveals an elevated Firmicutes-to-Bacteroidetes ratio-a consistent hallmark of dysbiosis that correlates with alterations in gut microbiota-derived metabolites. Additionally, treatment with short-chain fatty acids stimulated the differentiation of the motoneuron-like NSC34 cell line. These findings shed light on the multifaceted nature of DCM, resembling a synaptopathy that disrupts cellular communication within the neuromotor axis while concurrently exerting influence on other systems. Notably, the colon emerges as a focal point, experiencing substantial perturbations in both mucosal barrier integrity and the delicate balance of intestinal microbiota.

Deep Learning Algorithm for Identifying Cervical Cord Compression Due to Degenerative Canal Stenosis on Radiography

STUDY DESIGN

Cross-sectional study.

OBJECTIVE

Validate the diagnostic accuracy of a deep-learning algorithm for cervical cord compression due to degenerative canal stenosis on radiography.

SUMMARY OF BACKGROUND DATA

The diagnosis of degenerative cervical myelopathy is often delayed, resulting in improper management. Screening tools for suspected degenerative cervical myelopathy would help identify patients who require detailed physical evaluation.

MATERIALS AND METHODS

Data from 240 patients (120 with cervical stenosis on magnetic resonance imaging and 120 age and sex-matched controls) were randomly divided into training (n = 198) and test (n = 42) data sets. The deep-learning algorithm, designed to identify the suspected stenosis level on radiography, was constructed using a convolutional neural network model called EfficientNetB2, and radiography and magnetic resonance imaging data from the training data set. The accuracy and area under the curve of the receiver operating characteristic curve were calculated for the independent test data set. Finally, the number of correct diagnoses was compared between the algorithm and 10 physicians using the test cohort.

RESULTS

The diagnostic accuracy and area under the curve of the deep-learning algorithm were 0.81 and 0.81, respectively, in the independent test data set. The rate of correct responses in the test data set was significantly higher for the algorithm than for the physician's consensus (81.0% vs . 66.2%; P = 0.034). Furthermore, the accuracy of the algorithm was greater than that of each individual physician.

CONCLUSIONS

We developed a deep-learning algorithm capable of suggesting the presence of cervical spinal cord compression on cervical radiography and highlighting the suspected levels on radiographic imaging when cord compression is identified. The diagnostic accuracy of the algorithm was greater than that of spine physicians.

LEVEL OF EVIDENCE

Level IV.

Screening for degenerative cervical myelopathy with the 10-second grip-and-release test using a smartphone and machine learning: A pilot study

Objective

Early detection and intervention are essential for the mitigation of degenerative cervical myelopathy (DCM). However, although several screening methods exist, they are difficult to understand for community-dwelling people, and the equipment required to set up the test environment is expensive. This study investigated the viability of a DCM-screening method based on the 10-second grip-and-release test using a machine learning algorithm and a smartphone equipped with a camera to facilitate a simple screening system.

Methods

Twenty-two participants comprising a group of DCM patients and 17 comprising a control group participated in this study. A spine surgeon diagnosed the presence of DCM. Patients performing the 10-second grip-and-release test were filmed, and the videos were analyzed. The probability of the presence of DCM was estimated using a support vector machine algorithm, and sensitivity, specificity, and area under the curve (AUC) were calculated. Two assessments of the correlation between estimated scores were conducted. The first used a random forest regression model and the Japanese Orthopaedic Association scores for cervical myelopathy (C-JOA). The second assessment used a different model, random forest regression, and the Disabilities of the Arm, Shoulder, and Hand (DASH) questionnaire.

Results

The final classification model had a sensitivity of 90.9%, specificity of 88.2%, and AUC of 0.93. The correlations between each estimated score and the C-JOA and DASH scores were 0.79 and 0.67, respectively.

Conclusions

The proposed model could be a helpful screening tool for DCM as it showed excellent performance and high usability for community-dwelling people and non-spine surgeons.

Development and testing of a new application for measuring motion at the cervical spine

Background

Cervical myelopathy is a progressive disease, and early detection and treatment contribute to prognosis. Evaluation of cervical intervertebral instability by simple X-ray is used in clinical setting and the information about instability is important to understand the cause of myelopathy, but evaluation of the intervertebral instability by X-ray is complicated. To reduce the burden of clinicians, a system that automatically measures the range of motion was developed by comparing the flexed and extended positions in the lateral view of a simple X-ray of the cervical spine. The accuracy of the system was verified by comparison with spine surgeons and residents to determine whether the system could withstand actual use.

Methods

An algorithm was created to recognize the four corners of the vertebral bodies in a lateral cervical spine X-ray image, and a system was constructed to automatically measure the range of motion between each vertebra by comparing X-ray images of the cervical spine in extension and flexion. Two experienced spine surgeons and two residents performed the study on the remaining 23 cases. Cervical spine range of motion was measured manually on X-ray images and compared with automatic measurement by this system.

Results

Of a total of 322 cervical vertebrae in 46 images, 313 (97%) were successfully estimated by our learning model. The mean intersection over union value for all the 46-test data was 0.85. The results of measuring the CRoM angle with the proposed cervical spine motion angle measurement system showed that the mean error from the true value was 3.5° and the standard deviation was 2.8°. The average standard deviations for each measurement by specialist and residents are 2.9° and 3.2°.

Conclusions

A system for measuring cervical spine range of motion on X-ray images was constructed and showed accuracy comparable to that of spine surgeons. This system will be effective in reducing the burden on and saving time of orthopedic surgeons by avoiding manually measuring X-ray images.

Trial registration Retrospectively registered with opt-out agreement.